Dual ignition system.



R H. CUNNINGHAM. DUAL IGNITION SYSTEM. 7

APPLICATION FILED FEBJ, 1910.

Patented Apr.-9, 1912.

i lwwooeo RICHARD H. CUNNINGHAM. OF NEW YORK, N. Y.

DUAL IGNITION SYSTEM.

, Specification of Letters Iatent.

Patented Apr. 9, 1912.

Application filed February 9,1910. Serial No. 542,879.

To all whom it may concern:

Be it known that I, RICHARD H CUN- 'INoHAina citizen of the United States, residing at the city of New York, in the borough of Manhattan and State of New 'York, have invented certain new and useful Improvements in Dual Ignition Systems, of which the following is a full, clear, and exact description;

This invention relates to combined ignition systems, and more particularly to such a system comprising a self-contained high tensionmagneto dynamo to be used in connection with internal combustion engines for effecting ignition therein.

The object of the system and the devices comprised in the same is to fire the charge of explosive gas in an enginewhen the latter is at rest by causing ,a spark tobe produced by making circuit from a suitable battery for a brief instant, and then immediately interrupting the current, said current invariably passing through the primary winding of the high tension magneto armaturein such manner that demagnetization of the permanent magnets is substantially impossible when said armature is. in its usual resting position, and whenproperly timed with respect to the usual upright four cylinder four cycle engine.

A further object is to pass said current through the armature, and therebyby electromagnetic force strengthen the permanent magnets forming the field of the magnet. Further, -to so conductthe battery current-through the armature, that at very 'slow speeds, as for example when starting large engines of great compression, the bat.

tery current will augment or boost that of the magneto, and on being interrupted will produce a powerful secondary spark in the engine cylinder at exactly the correct moment.

Other objects of my invention will be hereinafter set forth and particularly pointed out in the appended claims.

' Referring to the drawingwhich forms a part of this disclosure, and which diagrammatically illustrates the arrangement of the the magneto poles shown therein have been several parts and connections th'erebetween,

secondary Winding 5 is also wound upon said reduced portion, one end thereof being grounded at 6 as shown,wwhile the other end of said secondary coil is in electrical connection with the usual bronze sector 7 of a distributer 8, the latter being of the usual construction and provided with four contact successively with the extremity of sector 7. The several plugs 9 are respectively connected to terminals 10 bywhich the secondary current may be led to the spark plugs of the respective cylinders in the usual manner. The armature shaft which is of the shown, carries thereupon a commutator 11, which I preferably form with two segments 12 suitably insulated from each other, by insulating strips 13, said strips being of somewhat greater width than the corresponding dimensions "of the brushes hereinafter described. The ends of armature primary coil 4are respectively connected to the segments 12 at 14. Brushes of carbon or other material of any suitable construction, are provided in connection therewith, one of these brushes 15 being grounded as at 16; while the other brush 17 is insulatedly mounted as at-1 8'.

About the extremity of the armature shaft is placed the breaker box 18. This box is of peculiar construction which I do not specifically desire to claim in this application. Brieflydescribed, the box comprises a breaker bar 19 pivoted to the box casing at 20; a bracket 21 secured by bolt 22 or other suitable means to one side of said casing; a bracket 23 secured by screws 24 to said casing, said screws 24 being preferably of insulating material; and insulating lay- ,ers 2526 are placed respectively between the casing and brackets 23 and 21; An adjusting screw 27 is threaded through a pro- 31 projecting from the center of the end of the armature shaft. fiat spring 32 is -mounted upon bracket 23, being suitably insulated therefrom as at '33. A somewhat lsimilar'but heavier spring 34 is secured dilugs 9, which are adapted to. make contact cam which is mounted upon a pin or bolt usual description and has hence not been rectly to a portion of said bracket 23, to provide electrical contact therewith. Contacts 35 and 36 are respectively mounted upon the inner sides of springs 33and 34, so that pressure upon the fiber button 37 which is carried upon the upper side of the spring 32, will cause the engagement of said contacts. This engagement is effected by the rotation of the armature shaft causing the ovoid cam to engage the button .37, and depress the same twice in every revolution of the armature of said shaft. Brackets 21 and are electrically connected by a wire 38, and a lead 39 electrically connects spring 32 with the inner extremity of an insulatedly mounted binding post 40. The breaker bar 19 is grounded and hence is in electrical connection with brush 15. A battery 41 of any suitable description is provided, and a switch 42 provided with six contacts respectively designated 43, 44, 45, 46, 47 and 48, is electrically connected to said battery and to the magneto circuit that when turned into the position indicated in fulllines in the drawing and marked Bat. will throw the said battery into circuit in the manner hereinafter described.

When the switch is in theposit-ion indicateIl by dotted lines 49 marked Mag. the battery is cut out of circuit. A flying,

vibratory-contact button 50 and condenser 51 are shown in connection with the battery circuit. Button 50 may of course be made of the usual push button type, but in order to further conserve the battery and also to avoid any possibility of burning out the armature winding I have provided a flying contact button, the construction of which will be hereinafter described.

Considering now .the connections between the several parts: Brush 17 is electrically connected. to contact 46 by a lead 52. Binding post or screw 22 is connected to contact 45 by lead 53. Post 40 is connected to contact 44 by lead 54. The positive pole of the battery is connected to contact 43 by lead 55. A lead 56 similarly connects the negative pole with contact 48. Contact 43 is connected to the flying member of the push button 50 by a wire 57. Contact 45 is connected by a wire 58 to't-he stationary element of said button and the plates of condenser 51 are respectively connected to leads magneto gives an unidirectional pulsatory current which is interrupted as usual at its maximum.

. In four cylinder engines the crank shaft is substantially horizontally disposed when at rest, and the cam 30'is so arranged upon the armature shaft which is driven from said crank shaft that said cam will, when the engine is at rest be in substantially the position that is shown in the drawing. The breaker bar 19is therefore in its lowermost position, and contacts 27 and 28 in juxtaposition. Assuming the switch to be in battery position, a slight touch of the fingerupon button 50 will usually suflioe to start the engine, since an explosive mixture of gas .is normally under compression in at least one cylinder thereof, while the distributer will insure the formation of the ignition spark at. the'proper plug. Following now the course of the current due to the closure of the circuit by means of push button 50, said current will leave the positive pole of the battery to traverse lead 55, thence to contact 43. Current cannotpass along lead 54, screw 40, wire 39 and spring 32, by reason of the fact that springs 32 and 34 are out of contact by a space of perhaps 1/32nd of an inch, owing to the fact that button '37 is not engaged by cam 30 when the engine is at rest. Current may, however, follow lead 57 through the momentarily closed contacts of push button 50, lead 58, through contact 45, thence along lead 53 to post 22, to metallic bracket 21, through contacts 2728, breaker bar 19 to ground, thence from 16 to brush 15, the commut-atorsegment 12 in connection therewith, through primary winding 4, the remaining commutator segment, brush 17, lead 52, contact 46, lead 59, switch blade 61, contact 48 and lead 56, back to the negative pole of the battery. The condenser 51 prevents the plug 50 from being burned out even after long continued use.

The energizing of primary coil 4 in the manner justdescribed, induces current in the secondary coil 5, and sector 7, being always, when at rest, either in contact with or closely adjacent to one or the other of contacts 9, said secondary current will pass to the respective terminal 10 leaping the gap between the sector 7 and the corresponding sify the magnetic field of the magneto.

After the engine hasstarted, current from made between cont-acts 35 and 36, the cur-- rent will pass therethrough and from thence to 34, 23, 38, 21, 27, 28, 19 to ground, from ground at 16, to brush 15, through commutator segment 12, primary winding 4, re-

malning segment 12, brush 17, 52, 46, 59,61,

48, 56, back to the negative terminal of the a battery. I'This circuit is only possible when both sets of contacts, namely 35 and 36, and 27 and 28, are in contact, but said contacts are so positioned for but a very small fraction of each half revolution of the engine shaft. The breaker box therefore aflfords us the utmost economy of operation on the batte y side. Assuming now that the switch is.

turned to magneto position, the current will traverse the parts numbered as follows: 4, 12,17, 52, 46, 60, 45, 53, 22, 21, 27, 2s, 19, to ground, 15, 12 and back to a, In this case the contacts 35 and 36 are not in use. To prevent arcing at the contacts, no matter by what means the current through the coil is interrupted, I prefer to place the post 22 in electrical connection with a suitable condenser 63, the otherside of said condenser being connected to ground at 64:. This places condenser 63 directly across the point of rupture of the current: In connection with the changing polarity of the armature, it is to be observed that the circuit through .the primary winding is broken just as the edge of the armature leaves the pole piece, and that this circuit stays open until the rotating armature is again nearly horizontal. As the width of the insulation between the commutator sections is greater than the width of the brushes short cireuitingv of the battery cannot occur; and it is further desirable to so arrange the position of the commutator parts with respect to the cam 30, that no current can flow through the circuit at the instant when the commutator segments are leaving the brushes, and hence the only wear upon such parts is that due to friction alone, arcing being impossible.

The following is a brief description of one screw 66, and one extremity of member 65 is bent .backupon itself and thence down ward as at 67 A long resilient tongue 68 is struck up from the body of member 65 anti is bent in the manner shown, the lower port tion thereof extending substantially hori'- zontally.- The end of this horizontal portion is adapted to engage a pocket 69 in the sloping wall 70 of the box 65. Contact screw 71 extends through the bottom of said box and is so positioned with respect to the horizontal portion of tongue 68 that when button 50 is depressed, thereby bending tongue 68, and after the end 67 has forcibly disengaged the end of said tongue from its seat in pocket 69, said tongue willresiliently fly out and make a series of momentary flying contacts with said contact screw.

It is obvious that the various portions of the tongue 68 will first swing downwardly and to the left when button 50 is depressed and after the end of said tongue has been disengaged in manner aforesaid, since the greatest flexure of the body of member 65 will occur between the base of the, notch formed by striking up tongue 68 and the upper edge of the left hand wall of the box cavity. The extremity of the tongue 68 will hence travel in a path which will be approxi;

which will lie substantially midway between.

the base of the tongue and the edge of the wall aforesaid so that the end of said tongue will, inoperation, be displaced to the left a considerable amount. thereby leaving the tongue free to vibrate In the drawing, for purposes of illustration, the nose or end of the tongue is shown as extending over onto the floor of the pocket 69 an appreciable distance, but in pract cc of course the extent of the co-engaging surfaces of these parts would be but slight, and the parts are so proportioned that the tongue will be free to vibrate as aforesaid without contacting with the vertical an below the-edge of the pocket 69 when so acting: 'The number of vibrations which the tqngue can make after being started into operation is necessarily and properly limited and this serves to prevent inadvertent maintenance of the battery cir cuit for an indefinite time. In other words this device provides an auxiliary circuit closing means normally permitting but a limited number of momentary impulses of current through the primary winding when the armature is at rest.

The downwardly extending end 67 acts in the n'lanneudescribcd by reason of its engagement with the sloping wall. The floor of a recess 72 in the box wall limits the downward movement of button 50 and insures only a series, of momentary contacts between tongue 68 and contact 7-1. Any

vibratorily acting device may'however be used as the matter in this connection which I herein desire to protect resides in the combination in one system of manipulatable means for permitting but momentary impulses of current through a magneto primary when the engines are at rest, in combination with purely automatic means for permitting periodic current impulses to flow through said primary after the engines have been started.

In this system there can be no possible waste of battery current, nor can there be any over heating or burning out of the primary winding, whether the engine be at rest or in motion.

Having now described my invention, what I claim, is: a

1. In a-dual ignition system, a magneto comprising primary and secondary Windings, an external source of electricity in circuit with a primary winding of said magneto, a commutating device having contactable conductive elements in such. circuit, and means for preventing sparking at said commutating device when in operation, comprising contact making and breaking members also in the circuit aforesaid and cooperating timed mechanism for moving said members apart just before conductive elements-of said commutating device are separated,

2. In a combined ignition system, a magneto having an armature comprising primary and secondary windings, a distributor in circuit with said, secondary winding, a battery, means for throwing said battery in circuit with said armature primary winding, a commutator in said circuit and a breaker box comprising means including a revoluble member for ai'itomatlcally and periodically interrupting current through said primary winding regardless of the luble member, for economizing the flow of current from said battery when the latter is in circuit.

3. In a combined ignition. system, a current generating apparatus including a primary and secondary winding, a distributer in circuit with said secondary winding, a battery, means for throwing said battery in circuit with said primary winding, a commutator in said circuit and a circuit breaking appliance comprising an actuating member, and a movable contact for periodically interrupting current through said primary winding regardless of the source of current therethrough, said appliance further comprising additional circuit making and breakmg parts, one at least of which is displaceable by said actuating member immediately before the actuation of the movable contact aforesaid, whereby to economize the flow of current from said battery when the latter is in the circuit.

In witness whereof, I subscribe my signature, in the presence of two witnesses.

RICHARD H. CUNNINGHAM.

Vitnesses WVALno M. CHAPIN, M. A. ROSENBAUM. 

